As the supplier of nutrients to the brain, the cerebral vascular network is as crucial to normal brain function as the neurons themselves. This collaborative project aims to bridge computational and experimental approaches across neuroscience, biomedical imaging, and electrical and computer engineering to advance the fundamental understanding of coupling between neural and vascular activity at extensive spatial and temporal scales. The experimental study will focus on the rat somatosensory system with exposed cortical surface for optical access. We will develop laser speckle contrast and two-photon fluorescence imaging techniques for functional imaging of blood flow on the cortical surface at microvessel and millisecond scale resolution. The custom designed image sensor will be integrated in a micro-optic enclosure that facilitates in vivo studies in awake, behaving rodents. Experiments that utilize whisker stimulation and arterial blocking agents will supply valuable data to construct and validate spatiotemporal models of neurovascular coupling and hemodynamics in cortical arterial networks. We anticipate that this research will contribute to both fundamental advances in computational neuroscience studies of neurovascular dynamics in healthy brain, and biomedical aspects of diseased brain and its means of recovery. The research is significant in that it will explain at a quantitative level the mechanisms of blood flow and dilation in microvessels in relation to functional brain activity. This will lead to better quantitative understanding of the effect of 'blood steal'in functional magnetic resonance imaging (fMRI) of closely spaced regions of neural activity. Effects of stroke will be emulated by arterial occlusion to study reperfusion of affected brain areas. The significance of this study is that it allows to quantify the extent of spontaneous and drug-induced brain recovery after stroke, by observing changes in brain vascular activity in response to functional stimulation. The project provides unique opportunities for training of engineering and neuroscience students participating in an interdisciplinary and inter-institutional collaborative research program.